J. Edgar Hoover, Federal Bureau of Investigation (FBI) director, recommended Cohn to Joseph McCarthy, who was the chairman of the Senate's permanent investigations subcommittee and who like Richard Nixon had seen the electoral value of an anti-communism crusade. Cohn was named chief counsel to the subcommittee and Robert Kennedy was counsel of the Democratic minority.

See below the 2004 Finfacts article:The rise and fall of an Irish-American demagogue

Both Hoover and Cohn were closet gays and McCarthy may have been one as well. However, maybe over-anxious to show the "respectable" society that they were straights, there was also a parallel witch hunt against homosexuals led by Hoover while McCarthy was implicated in the blackmailing and subsequent 1954 suicide of a US Senate colleague whose son had been charged with being a homosexual. Years later, Cohn denied that he was "ever gay-inclined" according to The New York Times obituary.

Roy Cohn, the lurking legal hit man for red-baiting Sen. Joe McCarthy, whose reign of televised intimidation in the 1950s has become synonymous with demagoguery, fear-mongering and character assassination. In the formative years of Donald Trump’s career, when he went from a rich kid working for his real estate-developing father to a top-line dealmaker in his own right, Cohn was one of the most powerful influences and helpful contacts in Trump’s life.

Over a 13-year-period, ending shortly before Cohn’s death in 1986, Cohn brought his say-anything, win-at-all-costs style to all of Trump’s most notable legal and business deals.Interviews with people who knew both men at the time say the relationship ran deeper than that — that Cohn’s philosophy shaped the real estate mogul’s worldview and the belligerent public persona visible in Trump’s presidential campaign.

“Something Cohn had, Donald liked,” Susan Bell, Cohn’s longtime secretary, said this week when I asked her about the relationship between her old boss and Trump.

She had been summoned to a lunch meeting with her husband-to-be and his lawyer to review a prenuptial agreement.It required that, should the couple split, she return everything — cars, furs, rings — that Mr. Trump might give her during their marriage.

Sensing her sorrow, Mr. Trump apologised, Ivana Trump later testified in a divorce deposition. He said it was his lawyer’s idea.

“It is just one of those Roy Cohn numbers,” Mr. Trump told her.

The year was 1977, and Mr. Cohn’s reputation was well established. He had been Senator Joseph McCarthy’s Red-baiting consigliere. He had helped send the Rosenbergs to the electric chair for spying and elect Richard M. Nixon president.

Then New York’s most feared lawyer, Mr. Cohn had a client list that ran the gamut from the disreputable to the quasi-reputable: Anthony (Fat Tony) Salerno, Claus von Bulow, George Steinbrenner.

But there was one client who occupied a special place in Roy Cohn’s famously cold heart: Donald J. Trump.

In October 1973, when Trump and Cohn first met at Le Club, the lawyer was instantly recognizable, with piercing blue eyes, heavy eyelids and a perpetual tan. James D. Zirin, a New York lawyer who later wrote about Cohn, recalled him as “the strangest-looking man I ever met,” with a face “contorted in a perpetual ugly sneer that seemed to project an air of unbridled malevolence.” Trump, not yet a household name, knew about Cohn’s reputation as a legal knife fighter.

At the time, Trump and his father, Fred, were facing Justice Department allegations that they had systematically discriminated against black people at their family-owned or -managed apartment complexes across New York City. Cohn agreed to represent the Trumps — his way. That meant hitting back hard while shaping public opinion. On Dec. 12, 1973, Donald Trump, his father and Cohn called a news conference at the New York Hilton hotel. They said they were suing the government for $100 million in damages relating to the Justice Department’s “irresponsible and baseless” allegations.

Cohn went further in an affidavit, saying the government was really trying to force “subservience to the Welfare Department,” according to court records.

A federal judge dismissed the countersuit. And two years later, after a string of theatrics and unfounded allegations by Cohn — including the claim that a Jewish prosecutor had used Nazi Gestapo tactics — Donald and Fred Trump settled the case without admitting guilt.

They signed a consent decree prohibiting them from “discriminating against any person in the terms, conditions, or privileges of sale or rental of a dwelling.”

In recent years we have seen angry minds at work mainly among extreme right-wingers, who have now demonstrated in the Goldwater movement how much political leverage can be got out of the animosities and passions of a small minority. But behind this I believe there is a style of mind that is far from new and that is not necessarily right-wing. I call it the paranoid style simply because no other word adequately evokes the sense of heated exaggeration, suspiciousness, and conspiratorial fantasy that I have in mind. In using the expression “paranoid style” I am not speaking in a clinical sense, but borrowing a clinical term for other purposes. I have neither the competence nor the desire to classify any figures of the past or present as certifiable lunatics. In fact, the idea of the paranoid style as a force in politics would have little contemporary relevance or historical value if it were applied only to men with profoundly disturbed minds. It is the use of paranoid modes of expression by more or less normal people that makes the phenomenon significant.

Rob Brotherton, an academic psychologist and the author of 'Suspicious Minds: Why We Believe Conspiracy Theories' wrote last February that the market for conspiracy theories is mainstream:

Jesse Walker found so many examples woven so deeply into the fabric of America that he titled his book on the subject United States of Paranoia. In it, Walker pointedly subverted the title of Hofstadter’s famous essay by titling a chapter “The Paranoid Style Is American Politics.” The establishment, Walker points out, “has conspiracy theories of its own.” From the Declaration of Independence (which described “a design” to establish “absolute Tyranny over these States”) to President Obama (whose 2012 reelection campaign accused “secretive oil billionaires” of distorting his record and attempting to buy the election) — not to mention the many conspiracist musings of current Republican presidential frontrunner Donald Trump — conspiracy theories have always had a place at the heart of American politics.

The rise and fall of an Irish-American demagogue

June 2004: Fifty years ago, the early summer was a heady time in Washington DC. In the weeks following the historic Supreme Court ruling against segregation in public schools, the anti-communism crusade of Irish American senator Joseph Raymond McCarthy began to unravel. Ten days after the dramatic humiliation of McCarthy on national television, a United States senator shot himself dead in his office in the Senate Office Building — a victim of a related witch-hunt to McCarthy’s. Three days later on June 22, 1954 a CBS newscaster, who had been branded a communist following criticism of McCarthy on air, took his own life. There were many other victims of what had become a national panic.

Until the election of John Fitzgerald Kennedy as president, no other politician of Irish extraction had achieved a national impact comparable with McCarthy’s in twentieth-century America.

McCarthy had lived in an area called the "Irish settlement" in northeast Wisconsin, a region that was dominated by German, Dutch and Scandinavian settlers. His mother was Bridget Tierney who was a native of Ireland and his father Timothy was son of a post Famine-immigrant from Tipperary, and a German mother.

Joseph McCarthy was one of seven children and following wartime service in the Marine Corps, at the age of 38 he was elected a United States senator in 1946 as a Republican because he had reckoned that he had a better chance of winning, than as a Democrat.

The renowned American historian William Manchester who died on June 1, 2004, has written that McCarthy was "a prime specimen of what has been called the Black Irish: the thickset, bull-shouldered, beetle-browed type found on Boston’s Pier Eight and in the tenements of South Chicago." McCarthy’s ‘Irishness’ and anti-communism had endeared him to the Kennedy family. John Kennedy had called him "a great American patriot" and his brother Bobby had chosen him as godfather for his first child and had worked as a counsel on McCarthy’s congressional investigations’ committee.

In his early years as a senator, McCarthy had little impact. He drank heavily, gambled and acted as a paid lobbyist for a number of business corporations. Then as the 1952 election was drawing closer, he found a cause.

The panic about communist success in Eastern Europe, the fall of Nationalist China and the Soviet atom bomb test following betrayal of American nuclear secrets, had set off a firestorm of national insecurity. Against that backdrop, McCarthy had seen how Senator Richard Nixon had gained national prominence through the investigation of a charge of espionage against a State Department employee and on February 9, 1950 in Wheeling, West Virginia, McCarthy launched his crusade.

Waving his laundry list, he claimed to have the names of 205 known communists who were State Department employees. In the succeeding days as he continued a speaking tour, the number changed and as he was challenged to produce credible evidence in the remaining weeks of February, McCarthy could not name one current suspect employee in the State Department.

According to William Manchester, McCarthy had phoned a Chicago Tribune journalist prior to his Wheeling speech and had been told of a 1946 letter from the secretary of state in which he had stated that an employee screening of individuals who had been transferred from wartime agencies had recommended against the permanent employment of 284 for various reasons. Of these, 79 had been discharged. McCarthy subtracted 79 from 284 and got his magical figure.

The bonfire that he’d lit, complete with lies, exaggerations and Senate investigations of his wild charges including one which dismissed them as a "fraud" and a "hoax," should have undermined his credibility but he soon became the most powerful American politician after the president. He was sustained by support from powerful media and wealthy pressure groups. Other politicians wilted in the face of McCarthy’s popularity and the Washington Post was one of the few significant newspapers that challenged him head-on. It’s cartoonist Herbert Block (‘Herblock’) gave a name to the tactics used by the junior senator from Wisconsin. Block produced a cartoon with ‘McCarthyism’ crudely lettered on a barrel of mud supported by ten mud-bespattered buckets.

While the Soviets had a long-term programme of infiltration in the United States, tarring anyone with being a sympathiser of what could be termed a left wing cause was virtually a sentence of death. Loyalty programmes and blacklists became important features of this shameful period and hundreds of artists — writers and entertainers were a particular target. Labelled communist sympathisers, passports were taken away and some were jailed for refusing to give the names of alleged communists. In these years of hysteria, communists were not the only targets.

McCarthy had claimed that there were "links between homosexuality and communism" and this was one issue where he had plenty competition from other legislators. A Senate subcommittee launched an investigation after a Washington DC vice squad officer told senators that there were 5,000 "perverts" in Washington, 4,500 of them employed by government agencies. It is ironic that apart from questions about McCarthy’s own sexuality, it was the favours that his young chief counsel Roy Cohn had sought for a male friend who had been drafted into the US Army that had set in train McCarthy’s ultimate political destruction.

The Army-McCarthy Hearings began in Washington DC in April 1954 with gavel-to-gavel coverage on national television. The purpose of the inquiry was to examine charges made by both sides including McCarthy’s claim that a spy ring existed in the Army Signal Corps. McCarthy’s rude outbursts and his ‘point of order’ interjections, which became a national catchphrase, exposed him as a fraud and bully.

On Wednesday, June 9, 1954, the hearings hit an emotional climax when McCarthy who was riled by innuendo about the nature of the relationship between Cohn and his enlisted Army friend, claimed that a young lawyer in the office of Army counsel Joseph Welch had been a member of an organisation that was the legal bulwark of the Communist Party."Until this moment, Senator, I think I never gauged your cruelty or recklessness...Have you no sense of decency, sir at long last? Have you no sense of decency?" Welch asked and then cut off McCarthy as he tried to intervene. Welch called for the next witness and the public gallery burst into applause. The hearings were adjourned and as a bewildered McCarthy sat alone at the coffin-shaped table in the Senate Caucus Room, he held up his hands and asked, "What happened?" — see YouTube video evidence of hearingsPart 1 and Part 2.

On June 8, 1954, the day before McCarthy’s humiliation, Senator Lester Hunt, a Democrat from Wyoming had announced his decision not to seek re-election in the November elections. Control of the Senate had been finely balanced and Hunt had earlier resisted pressure to retire from Republicans following the arrest of his son for propositioning an undercover cop in Lafayette Park, near the White House. Hunt was a foe of McCarthy and a senator friend of Roy Cohn offered to have the case dropped against Hunt’s son in return for retirement from the Senate. The case went ahead and given the contemporary hysteria about homosexuals, it had a serious impact on Senator Hunt’s health. On Saturday June 19, 1954 Senator Hunt brought his hunting rifle to the US Capitol to take his own life.

On June 1, 1950 Republican Party senator Margaret Chase Smith of Maine, the only female member of the Senate, had issued a "Declaration of Conscience" asserting that because of McCarthy’s tactics, the Senate had been "debased to the level of a forum for hate and character assassination."

More than four years later, emboldened by the public reaction to McCarthy’s exposure on national television, other Senators found the backbone to challenge McCarthy and on December 2, 1954 the Senate voted 65 to 22 to condemn him for "conduct that tends to bring the Senate into dishonor and disrepute."

Senator John F. Kennedy was one of only three Democrats who did not vote for the censure motion.He was in hospital recuperating from back surgery and was working on his book 'Profiles in Courage' in which he chose eight of his historical colleagues to profile for their acts of astounding integrity in the face of overwhelming opposition. Senator Kennedy did not take a public position on the censure of McCarthy until 1956 when he was eager to become the Democrats’ vice presidential candidate.

The Wisconsin senator became increasingly dependent on alcohol, in the aftermath of his censure, as his name became a byword for demagogic slander.

The American writer Sam Tanenhaus has written that McCarthy was a confusing self-contradictory figure who had no coherent vision or programme. There was an element of the poor farm boy taking on the privileged Eastern liberal establishment but he had neither the talent nor interest in building a mass movement. While being an affable individual in private, he could not resist the lure of a headline at the expense of publicly bullying witnesses and jettisoning due process.Senator McCarthy died on May 2, 1957 of acute hepatitis at the age of 49, a discredited politician and the most hated senator in the history of the republic.

McCarthy took a serious issue, undermined it through reckless behaviour and destroyed the lives of many people in the process. On March 9, 1954, the leading American journalist of his day Edward R. Murrow in a closing commentary on CBS’ 'See it Now' TV programme said:

The line between investigating and persecuting is a very fine one and the junior senator from Wisconsin has stepped over it repeatedly...This is no time for men who oppose Senator McCarthy's methods to keep silent. We can deny our heritage and our history, but we cannot escape responsibility for the result.

For saying at the end of the programme, "I want to associate myself with every word just spoken by Ed Murrow," Don Hollenbeck CBS’ regular 11 pm newscaster sparked off a smear campaign in particular by the Hearst Press, that would end in his suicide.

This was the climate of terror that had been fanned by a onetime icon of Irish America.